Context

The backtrace also indicates, that you may be use Qt with accessibility enabled. If this is the case, please ask in the forums of your distribution how to disable Qt accessibility, and report back, if this fixes the issue.

Wished behavior

I wish "Qt accessibility off". That may mean not having this applet running.

Solutions already tried

Looking in KDE preference panel. There is an accessibility group (visual bell, modifier keys, keyboard filter), seems unrelated to "qt accessibility", does not mention the applet.

4 Answers
4

If everything fails, check which package installs
/usr/lib/x86_64-linux-gnu/qt4/plugins/accessiblebridge/libqspiaccessiblebridge.so
and try to remove it. If you cannot, because of dependencies, you can
manually move the file away as root, and restart the desktop. This
should remove support for Qt accessibility.

On Ubuntu 12.04 that boils down to sudo dpkg --purge qt-at-spi which effectively disables Qt accessibility.

This is a bit brute force (for example, it does not allow to enable accessibility for some users only), but it does answer the question with an effective solution, right ?

Did not work (apparently qt-at-spi is not the package) , I had to apply @Mattmon's hack.
– razorJan 30 '13 at 2:21

It was tested on 12.04 amd64. The package still exists in 12.10. What distribution do you use ? What do you mean by "did not work" ? No such package, or removal ok but problem remains ?
– Stéphane GourichonJan 30 '13 at 6:56

Interesting: this is a hack (and will probably cause some errors in .xsession-errors log). But if you need to keep accessibility enabled for some users, you can create a group and make the file executable only for that group.
– Stéphane GourichonJan 9 '13 at 19:56